1. Field of the Invention
The present invention relates to an image forming apparatus. More particularly, the present invention relates to an improved process cartridge removably mounted in an image forming apparatus, and an image forming apparatus having the same.
2. Description of the Related Art
Image forming apparatuses refer to devices which use an electrophotographic process, such as a photocopier, a printer, a facsimile and a word processor. A process cartridge is a kind of a subassembly detachably mounted to a main assembly, which integrally comprises a photoconductive medium, an electrifying unit, a developing unit and a cleaning unit.
The image forming apparatus using the electrophotographic process generally uses a process cartridge. Since the process cartridge enables a user to operate the apparatus without a special skill, thereby improving operability, image forming apparatuses employing the process cartridge are being widely used.
The process cartridge comprises a photoconductive unit, a developing unit and an opening/closing unit for opening and closing a waste toner outlet provided to the photoconductive unit.
The photoconductive unit comprises a photoconductive medium where an electrostatic latent image is formed and a photoconductive unit frame having the waste toner outlet for discharging a waste toner. The developing unit comprises a developing roller, a developing unit frame for supporting the developing roller, and a waste toner storage for storing the waste toner discharged through the waste toner outlet of the photoconductive unit. Preferably, the photoconductive unit and the developing unit are separably connected to each other.
As shown in FIG. 1A and FIG. 1B, the opening/closing unit comprises a shutter 10 mounted to the photoconductive unit frame 1 to move between first and second positions, thereby opening and closing the waste toner outlet 2, an elastic member 20 for elastically biasing the shutter 10 toward the second position where the waste toner outlet 2 is closed, and an opening/closing member 30 for moving the shutter 10 to the first position where the waste toner outlet 2 is opened.
The opening/closing member 30 operates in association with opening and closing of a door (not shown) of the image forming apparatus. For example, when the door (not shown) is closed, the opening/closing member 30 moves the shutter 10 toward the first position, as shown in FIG. 1B. Whereas, when the door (not shown) is open, the opening/closing member 30 returns the shutter 10 to the second position by the elastic recovery force of the elastic member 20, as shown in FIG. 1A.
However, in the conventional process cartridge of the image forming apparatus as the above, especially, if the photoconductive unit and the developing unit have different lifespans from each other, the waste toner may leak when a user separates the developing unit for replacement and closes the door, when the process cartridge is mounted in the image forming apparatus, since the shutter 10 moves to the first position by the opening/closing member 30, thereby opening the waste toner outlet 2. The leakage of toner may contaminate the inside of the image forming apparatus, and accordingly deteriorate image quality.